Design Of Cell Voltage Monitor System On Fuel Cell Stack And Fault Diagnosis Research

Along with the quantity of automobile growth in our country, the automobile discharges the pollution seriously day by day, the supply and demand contradictory of traditional automobile fuel is also becoming more prominent. Fuel cell electric automobile is the most realistic way to solute automobile exhaust pollution and fuel question. With the development of industrialization of Fuel cell, voltage monitor system of fuel cell pieces, as one of the crucial measure systems, is more and more important. Voltage monitor system of fuel cell pieces is not only very important at the stage of research and development of fuel cell stack but also important after implication. Because it is crucial in keeping fuel cell stack run formally. This paper takes the pieces voltage measure of fuel cell stack as research object. Develop the design of voltage monitor system of PEMFC pieces and fault diagnosis research. The main research contents as follows:This paper has introduced the main structure of Fuel Cell Electric Vehicle, and particularly describes the construction of fuel cell engine. On the basis of these, according to the function needs of the system and the special applied environment, this paper has designed a structure of monitor system based on 2-layer CAN network. The CAN subnet of the voltage measure unit and the fiber main CAN of automobile, these two nets are independent, and constitute reliable topologies net.On the basis of analysis of principle about voltage monitor of fuel cell pieces, this paper designs the hardware of high precision voltage measure unit, high speed network control unit and the interface circuit of LCD display and keyboard hardware. This paper also analyses their structures and characters detailed.This paper finished the software design of high precision voltage measure unit, high speed network control unit and the interface circuit of LCD display and keyboard. It made the application layer protocol of CAN and SCI, and designed the perfect function software of PC.Combining the applied situation of monitor system, this paper discussed fault diagnosis method of monitor system on the basis of fault tree. It analyzed the fault tree structure of voltage measure unit and network control unit, and realized logical reasoning fault diagnosis according to programming on single-chip. The fault diagnosis result is displayed on LCD.The whole monitor system uses distributed measure way, it has high reliability, good expansibility, so better realizes the real-time and high precision measure on voltage of fuel cell pieces. The system has independent intellectual asset, it has applied in "CHU TIAN YI HAO" fuel cell electric vehicle, fuel cell BUS and 50KW fuel cell measure plat of the material complex new technology national key lab in Wu Han University of Technology, and it has got a good performance.